Field of the Invention
The present invention generally relates to a lock-up device which utilizes a ball and cam arrangement to interlock two members. The interlocked members include ball engagement surfaces which are concave so that a substantial portion of the ball surface is in contact with the engagement surfaces. More particularly, the invention relates to a firearm having a ball and cam-type lock-up mechanism to withstand high chamber pressure when the firearm is discharged and also to store inertial force from recoil which is utilized by linear reaction to unlock the mechanism and cycle ammunition, without rotational movement. It should be noted that the word firearm is being used in this application to mean any device which discharges a projectile by use of an explosive charge.